用值来综合评估燃煤锅炉排放烟气污染程度的可行性

Feasibility of Using Exergy to Assess Air Pollution Level around a Smokestack

目的用一个参数值来评估一个大型燃煤锅炉所排放烟气中温度和化学物(SO2、NO、CO2)各自和综合污染分布特性,简化实际污染评估手段.方法通过数学模拟的方法建立大型锅炉烟气排放分析模型、建立排放烟气的温度分布、质量浓度分布、分布数学模型,并把所得的3种分布结果及特性进行比较.结果给出锅炉烟气排放分析模型中烟气的温度污染和主要排放物CO2,SO2,NO2的化学污染的火用值在排放高度、离地10m高度、和地面上沿风向分布的轴向模拟分析曲线、烟气的温度和主要排放物的浓度的分布曲线;找出烟气在3个不同高度污染的特点、污染的最严重地点,检查总污染的火用指标与各污染物单独评价指标的异同.结论得出仅用参数值作为污染评估值来评估排放烟气污染是完全可行的,而且充分显示了一个能联系不同自然学科,并在不同学科中自由转换的参数值火用作为污染评估标准的优越性.即可以把不同污染物的污染特性综合起来,集复杂的多种评估参数为一体,简化评估手段和方法,易于找到多种污染的最不利点.

The paper uses exergy as a combined standard to assess the pollution properties of pollutants emitted from a big coal-fired boiler.It models the distributions of temperature,concentration,and exergy of emitted gases from the smokestack.It analyzes and compares the exergy distribution characteristics of each single pollutant emitted from smokestacks,such as SO_2,NO,CO_2,and heat,and also combined ones.The results are compared with temperature difference distribution and concentration distributions of the pollutants at ground level,10 m height level,and effective height level separately.The conclusion is that one value __the exergy,can be a pollution assessment standard to show every pollution property of pollutants emitted from a boiler perfectly.It can also show the combined properties of pollutants in one curve and with one unit which can never be possible for simply adding temperatures and concentrations.The method simplifies the assessment variables and calculation steps,and with which the most hazardous places can be easily spotted.